Abrasive wheels



Aug. 9, 1960 C. KLINGSPOR ABRASIVE WHEELS Filed Jan. 13, 1959 Figa@Milou/V llnited States Patent.

ABRASIVE WHEELS Carl Klingspor, Waldstrahe `13a, Siegen, Westphalia,Germany Filed Jan. 13, 1959, Ser. No. 786,588 lClaims priority,application Austria Jan. 15, 1958 Claims. (Cl. 51-193.5)

This invention relates 'to abrasive wheels formed by rotary abrasivemembers comprising abrasive flaps of abrasive linen or a similarflexible material, which are unilaterally inserted in a .carrying ringwith freedom of oscillation. Such members are known for grinding and,where a suitable abrasive is selected, also for polishing work. Theseabrasive members, however, have the disadvantage that when constructedin large widths by arranging several such abrasive ap carrying ringsside by side they produce grinding marks at the joints of the severalrings. On the other hand, it is not possible to use the abrasive tiapsthemselves in the desired width and it has been found that abrasiveflaps having a width in excess of approximately 300 mm. give rise tovarious difficulties.

The present invention shows how abrasive wheels of any desired workingwidth can be obtained by arranging several abrasive flap carrying ringsside by side. rThis assembly may be effected by the user himself. Inorder to achieve this object the invention proposes a specialconstruction of the ring which carries the abrasive flaps.

According to the invention 4the abrasive wheel is characterized in thatthe abrasive liaps are arranged on each carrying ring in the form of ahelix, the length of which may be between a fraction of a full turn andseveral turns, and each carrying ring is bounded at its ends by helicalsurfaces of appropriate length. For instance, the carrying ring may havea circumferential length of 360 and form an offset or recess whose depthcorresponds to the lead of the helix in order to enable the assembly ofa plurality of such rings having mating recesses to form an abrasivewheel of increased working width.

The invention will be explained more fully with reference to theaccompanying diagrammatic drawings wherein:

Fig. 1 is a sectional view showing an abrasive member according to theinvention, with closed boundary faces which extend in accordance withhelices at the ends to form the above-mentioned recess.

Fig. 2 is an end view of the structure of Fig. l.

Fig. 3 is a partly sectional view showing diagrammatically an abrasivewheel having aps and rings forming several (approximately tive) helicalturns.

Fig. 4 is another partly sectional view showing how individual abrasiverings as shown in Figs. l, 2 can be af- Xed to a grinding spindle.

Fig. 1 and 2 show an abrasive member which comprises a helical carryingring 1, the ends of which are bounded by helical surfaces 2. Thesesurfaces have the lead a which is less than the width of the ring 1 sothat two steps or recesses 2a and two projections 2b are formed. Thecarrying ring 1 preferably consists of a plastic substance, but it mayalso consist of a metal with low melting point or another suitablematerial; the several substantially radial abrasive flaps 4 are embeddedin this material. 'Ihese aps consist of abrasive linen of appropriategrain size, abrasive paper or the like. The aps being iden- ICC tical inform, their side edges 4a lie also on helical surfaces, whereas theirend edges 4b lie on a cylinder. It will be appreciated that severalabrasive members having the form apparent from Figs. 1, 2 may be closelyaligned adjacent to each other-on a shaft, the projections 2b of onecarrying ring being received in the recesses 2a of the adjacent retainerring. It is'also apparent that such an abrasive wheelor screw composedof several abrasive members is suitable for the machining of surfaceshaving a corresponding Width without forming grinding marks because thejoints between the individual rings formed between the abrasive iiapsfollow a (stepped) helix.

IInstead of combining several loose rings as shown in Figs. 1, -2 toform a composite abrasive wheel the circumferential length of the rings,which is 360 in the example of Fig. l, may be increased -to a multipleof this value to provide a helix having several turns by adhesivelyconnecting `a plurality of rings as shown in Fig. 1 to form a screw. Anexample of this type is illustrated in Fig. 3. The resulting helix iscarried by a support 10 having supporting flanges 10a which extend inaccordance with an appropriate helical surface, and is forced againstthese flanges by a second support 11 having appropriate supporting anges11a. The retaining means or supports 10, 11 may be forced against eachother in any suitable way or may be affixed to the grinding spindle 12by means of a nut and lock nut (not shown).

Fig. 4 shows another fixation of the several abrasive rings -to agrinding spindle 13. Each group of abrasive flaps 4 forming part of anabrasive members has at its ends a closed annular groove formed by therecesses 14, see also Figs. l, 2 and 3. Gripping or retaining rings 15are provided, each of which consists of a hollow cylindrical hub 15ahaving a helical retaining rib whose ange 15b tits into the groovesformed by recesses 14 in the flaps 4 of two adjacent abrasive members sothat it can be screwed into the same. The configuration of theseretaining ribs and of their flanges 15b is diagrammatical- 1y shown indash lines in Fig. 4. The abrasive rings 1 may be screwed onto thegripping or retaining rings 15 in such a manner that each abrasive ring1 has a gripping or retaining ring 15 associated therewith, the latterrings being axially aligned on the grinding spindle 13 and being axiallyforced together on the same by suitable means. In the illustrativeembodiment shown it would be necessary, therefore, to force the grippingrings 15 by a nut (not shown), which is carried by the screw thread 13a,against the collar 13b of the shaft 13. Resilient inserts may beprovided between the end faces of adjacent gripping and retaining rings15 or a free space may be left between said end faces so that theabrasive rings are more or less compressed in the axial direction. It islthe object of all these measures to obtain a firm fixation of theannular or disclike abrasive members to a grinding spindle to ensure areliable retention of the abrasive members on the spindle even at highspeeds.

Appropriate molds are used in the manufacture of the present abrasivemembers. The abrasive flaps are inserted and xed in said molds,whereafter the carrying ring 1 is formed by casting so that the inneredges of the abrasive aps are embedded in the matrix forming the ring 1.

What is claimed is:

1. An abrasive wheel comprising, inl combination: a rotary spindle; aplurality of abrasive members mounted on the spindle, each membercomprising a continuous helical ring `of uniform Width bounded by a pairof helical end surfaces whose lead is less than the Width of the ringwhereby a recess and a projection is formed at each end of the ring, anda plurality of similar substantially radially arranged abrasive aps eachhaving an inner end embedded in the material of the the ring, the

iaps of each abrasive member forming a helix surrounding the respectivering and the aps of adjacent abrasive members forming a continuousmulti-turn helix about said spindle; and means `for retaining the ringsagainst rotation with respect-to said spindle.

2. An labrasive wheel as setfforth in claim 1, wherein said rings are of.pl-astic.

3. .An abrasive vWheel as set forth in claim 1, wherein the projections`of each ring extend into the recesses of adjacent rings and saidretaining means comprises a pair of flanged supports non-rotatably ixedto -the spindle and each bearing against an outermost ring for pressing.the adjacent rings toward each other.

4. An `abrasive Wheel as set forth in claim l, wherein said retainingmeans comprises an annular gripping rnernber for each ring, eachgripping member having a hub received in the respective rin-g andnon-rotatably surrounding said spindle, and a helical rib connected tothe hub and extending 'between the end surfaces'of adjacent rings forholding the rings against rotation with respect `to the spindle.

5. An abrasivel wheel as s'et forth in claim 4, wherein each flap has apair of side edges each formed with a recess, said last mentionedrecesses forming two helical grooves in the ilaps of each abrasivemember, and each gripping member yfurther comprising a helical iiangefixed to the rib and extending into the recesses of adjacent flaps.

References Cited in the file of this patent UNITED STATES PATENTS539,464 Whitaker May 21, 1895 1,628,352 Bonazzi May 10, 1927 2,651,894Leggett Sept. l5, 1953 2,678,523 Leggett May 18, 1954 2,802,315 BlockAug. 13, 1957

